System and method to enable wusb application in a distributed uwb mac

ABSTRACT

A system and method is provided for incorporating host-device communication in wireless USB (WUSB). A host ( 101 ) either uses a multicast Distributed Reservation Protocol (DRP) frame on behalf of connected devices ( 102 ) to reserve wireless channel resources, a unicast DRP frame or Enhanced Distributed Channel Access (EDCA) with a Poll Frame. In the case of a unicast DRP frame the number of unicast frames sent for reservation depends on the number of connected devices ( 102 ).

The present invention relates to a system and method for enablingwireless universal serial bus applications in a distributed ultrawide-band MAC.

Universal serial bus (USB) technology is a popular and effectivehigh-speed wired connection type for PCs that is migrating into theareas of consumer electronics (CE) and mobile devices. The nextgeneration of USB technology is wireless USB (WUSB) and will provide thefunctionality of wired USB without the inconvenience of wires and willbe based on ultra wideband UWB radio.

Referring now to FIG. 1, the typical or fundamental topology of WUSB isa hub-and spoke-architecture comprising a host 101 and at least oneconnected device 102. In this architecture, all traffic 103 is initiatedby the host 101 to its at least one connected device 102, by allottingtime slots and data bandwidth to each connected device 102.

The relationship between a host 101 and its at least one connecteddevice 102 is termed a cluster. The connections are point-to-pointbetween a WUSB host 101 and its at least one connected WUSB device 102.

A WUSB host 101 can logically connect to a maximum of 127 WUSB devices102, considered an informal WUSB cluster. WUSB clusters coexist withinan overlapping spatial environment with minimum interference, thusallowing a number of other WUSB clusters to be present within the sameradio cell.

The WUSB architecture supports dual roles for a device 102 wherein adevice 102 can also provide limited host capabilities. In this dual rolemodel, such a device/host can avail itself of the services of a centralhost 101 (i.e., printers) and can create a second cluster providingservices itself as a host for accessing data outside any existingcluster it is connected to. This architecture supports high spatialcapacity in small areas so that multiple devices have concurrent accessto high bandwidth.

In a wireless USB (WUSB) scenario there is one host 101 and one or moredevices 102 that transmit data to the host. In the wired USB scenariothe host sends a token or a poll frame to the devices to request datafrom the devices. It is expected that WUSB will use UWB MBOA MAC as ameans to communicate between a host 101 and connected devices 102 overthe wireless medium, see MBOA Wireless Medium Access Control (MAC)Specification For High Rate Wireless Personal Area Networks (WPANs),Technical Specification, Draft 0.5, April 2004, which is herebyincorporated by reference as if fully set forth herein. Since the UWBMBOA MAC is distributed, there needs to be a method by which a host canreserve channel resources on behalf of connect devices 102 so thatconnected devices 102 can transmit data when requested by the host 101.

In the MBOA MAC specification the medium can be reserved by means of the“Distributed Reservation Protocol” (DRP). This protocol comprises twomechanisms of negotiating a reservation of channel time: an explicitnegotiation by means of dedicated command frames, and an implicitnegotiation by inclusion of the DRP Information Elements (IEs) in thebeacon of sender and receiver's. In both cases, once the reservation isestablished, the reservation information is included in the beacon ofsender as well as receiver(s) in every superframe, in which thereservation is still active. This is necessary in order to informneighboring devices of sender and receiver(s) about the existingreservation. These neighboring devices have to store the reservationinformation received and abstain from medium access during the reservedperiod of time.

DRP reservations can be unicast or multicast reservations between two,respectively a group of devices.

Thus, there is a need for a system and method for UWB MAC to reservewireless channel resources so that connected devices 102 can send datato a host 101.

The present invention is based on a distributed UWB MBOA MAC that usesdistributed reservation protocol (DRP) to exchange both isochronous andasynchronous data. That is, the present invention relates to datatransfer between connected devices 102 and a host 101 that use the DRPprotocol. The present invention provides a system and method forincorporating DRP-based host-device communication in wireless USB(WUSB).

In a first embodiment, the host 101 uses a multicast DRP (distributedreservation protocol) frame on behalf of connected devices 102 toreserve wireless channel resources for data transfer between the host101 and connected devices 102 based on connected device characteristicsand what traffic they have.

In the second embodiment the host 101 sends a unicast DRP frame to aconnected device 102 and negotiates the use of channel resources fordata transfer between the connected device 102 and the host 101.

In a third embodiment the host 101 sends a Poll frame to a connecteddevice 102 to trigger the transmission from said device 102.

Thus, the present invention is a system and method for a distributed MACprotocol that provides a solution to incorporate WUSB data transfertherein.

Other features and advantages of the present invention will be obviousfrom the following drawings and detailed description of the invention.

FIG. 1 illustrates a typical hub-and-spoke WUSB architecture;

FIG. 2 illustrates a micro-scheduled DRP reservation according to theWUSB Working Group standard.

FIG. 3 a illustrates an architecture of a host according to the presentinvention;

FIG. 3 b illustrates an architecture of a connected device according tothe present invention;

FIG. 4 illustrates a finite state diagram (FSD) for host data transferprocessing.

It is to be understood by persons of ordinary skill in the art that thefollowing descriptions are provided for purposes of illustration and notfor limitation. An artisan understands that there are many variationsthat lie within the spirit of the invention and the scope of theappended claims. Unnecessary detail of known functions and operationsmay be omitted from the current description so as not to obscure thepresent invention.

The present invention provides a system and method for incorporating thehost-device communication in wireless USB (WUSB). Referring now to FIG.1, in a WUSB scenario there is one host 101 and one or more connecteddevices 102 that transmit data to the host 101. In the wired USBscenario the host sends a token or a poll frame to the devices torequest data from the devices. WUSB could use UWB MBOA MAC as a means tocommunicate to other devices over the wireless medium. The UWB MBOA MACis distributed and the present invention provides a system and a methodby which a host 101 can reserve channel resources on behalf of connecteddevices 102 so that connected devices 102 can transmit data whenrequested by the host. That is, the present invention is a system andmethod for reserving wireless channel resources so that connecteddevices 102 can send data to a host 101.

In a first embodiment, a host 101 of a WUSB initiates a multicast DRPframe to reserve wireless channel resources with/on behalf of at leastone WUSB device 102 connected thereto. Each of the at least one device102 that is connected to the host 101 communicates device 102characteristics to the host 101 that are used by the host 101 to reservewireless channel capacity on behalf of the at least one device 102. Oneadvantage of this embodiment is that the overhead of reservation is verylow, since the multicast reservation is done for multiple devices. Inaddition, a combined reservation by the host results in there being onlyone contiguous time period for the host 101 to receive data from the atleast one device 102. In this first embodiment, the contiguous timeperiod is scheduled for the at least one device using a protocol calledmicro-scheduling. The micro-scheduling protocol is defined in the “WUSBKey Developers, USB-IF, WUSB Micro-scheduling Specification, Revision0.5c, December 2003”, which is hereby incorporated by reference in itsentirety and is illustrated in FIG. 2. Micro-scheduling adds anefficient and extensible medium allocation mechanism for applicationsthat require lower latency and finer grained bandwidth control. UnderMicro-scheduling, the host reallocates the channel time within a DRPreservation on an intra-superframe basis. This allows the devices torapidly and efficiently change the amount of channel time allocated toother devices that are aware of and permitted to use the DRPreservation. The group using micro-scheduling is called amicro-scheduled cluster. The devices within the cluster that allocatesthe use of the medium within the micro-scheduled DRP reservation iscalled the Micro-Scheduled Cluster Controller (MSCC).

Thus, the multicast DRP protocol of the present invention is a way toincorporate into UWB MAC the existing micro-scheduling scheme of theWUSB specification. The disadvantage of this scheme is that the host 101must perform another multicast reservation or perform a unicastreservation for those devices 102 that did not agree with the initialmulticast reservation.

In a second embodiment, the host 101 initiates a separate unicast DRPreservation to the at least one device 102 to reserve channel resources.In this second embodiment, the number of reservation frames that need tobe sent on the channel is directly proportional to the number of devices102 connected to the host 101. This reservation initiation is equivalentto the micro-scheduled management command (MMC) of the current WUSBspecification. Once the reservation is made, the host 101 uses a pollframe to request the at least one device 102 to transmit data during thereserved period. Advantages of the second embodiment include (1) it is anatural extension of DRP and (2) WUSB devices can be very simple.However, higher DRP negotiation overhead is incurred (depending on thenumber of WUSB devices). And, because DRP reservations may be spreadthrough a superframe, this second embodiment may be less efficient thanthe micro-scheduling used by the first embodiment.

In a third embodiment, for WUSB transmissions that do not require DRP,the poll frame may also be sent by the host 101 using the EDCA channelaccess, that has control of the medium for a time specified by the EDCATXOP limit, to request that the at least one device transmit data. Thethird embodiment has the advantage of flexibility and does not requiredevices to support and implement DRP mechanisms. However, EDCA is acontention-based access and there are no guarantees against delays.

For each embodiment, the host 101 must know the capabilities of the atleast one device 102. These capabilities are included by the at leastone device 102 when the at least one device 102 transmits a Beacon. Thehost 101 also includes the host 101 capabilities in a Beacon. In eachembodiment, the devices 102 announce if traffic is pending to the WUSBhost 101. In each embodiment, WUSB device notification traffic can use aDRP reservation or device notification traffic can be sent using EDCA orusing some signaling in the beacon frames.

WUSB host discovery is done via a Beacon in which the host includes itscapabilities.

In order to achieve better packing and facilitate implementation, theOffset and Duration fields of a DRP reservation are preferably set to amultiple of “X”, where X is selected based on the combination of thedesired resolution of the DRP reservation and the size of the DRP slot.Typically, X=625 usec.

Referring now to FIG. 1, a typical WUSB network employs a hub-and-spokearchitecture having a host 101 as the hub and at least one connecteddevice 102 as a spoke. A typical WUSB host 101, according to the presentinvention, may include a host MAC module 300 with an architecture thatis illustrated in the block diagram of FIG. 3 a. A host 101 may includea host MAC module 300 having a controller 301 operatively coupled to atleast a transmitter 302, a host data transfer processing component 303comprising a host DRP processing module 303 aand a host devicenotification processing module 303 b according to the present invention,and a receiver 304. The transmitter 302 and the receiver 304 areoperatively coupled to an antenna 305. The host DRP processing component303 aprovides adaptive programming such that, for example, at least oneof multicast and unicast DRP processing is accomplished by the host 101for each connected device 102.

A typical WUSB connected device 102 may optionally include a morelimited version of the host MAC module 300 as device MAC module 350 withan architecture that is illustrated in the block diagram of FIG. 3 b.Each connected device 102 may include a device MAC module 350 having acontroller 352 operatively coupled to at least a transmitter 302, adevice processing component 353 comprising a device DRP processingmodule 353 a and a device notification processing module 353 b accordingto the present invention, and a receiver 304. The transmitter 302 andthe receiver 304 are operatively coupled to an antenna 305. The deviceDRP processing component 353 a provides adaptive programming such that,for example, at least one of multicast and unicast DRP processing isaccomplished by the device 102 in response to reservations made by thehost 101 and such that the connected device 102 further accepts orrejects a reservation made on its behalf by the host 101. In addition,if a connected device has additional capabilities for acting as a hostitself, there is an optional device/host subcomponent (not shown), ofeach the modules 353 a-b.

Referring now to FIG. 4, a finite state diagram (FSD) illustrates hostdata transfer processing 303 including DRP reservation functionality ofthe host DRP processing component 303 a. Once the WUSB host isinitialized 401, it starts beaconing 402 following the rules specifiedin the MBOA MAC. The beacon includes the WUSB host capabilities, so thatWUSB devices can find the WUSB host by means of regular MAC beaconreception. Once WUSB devices are initialized the devices follow thebeaconing rules of the MBOA MAC, and look for the beacon from WUSBhost(s).

The WUSB waits to receive the device notification traffic (DNT) via EDCAif DRP is not supported 403, or via EDCA or DRP if DRP is supported 405.Following the EDCA operation 403, once DNT traffic is received via EDCA,the WUSB host uses EDCA mechanisms to access the medium and to poll theWUSB devices 406 according to a third embodiment of this invention. Itshould be noted that DNT traffic might be received via EDCA 403 eventhough the WUSB host supports DRP.

If DNT traffic is received and DRP is supported WUSB host initiates theDRP data negotiation process 405.

-   -   If the WUSB host and devices support multicast DRP, the WUSB        host includes a DRP multicast reservation in the beacon 408.        Devices may adopt the reservation and include it in their own        beacons. If all devices adopt the multicast reservation the WUSB        host starts the micro-scheduling operation. If some devices do        not adopt the multicast reservation, because, for example, they        have a conflict with a neighbor's reservation, the WUSB host may        initiate a second WUSB multicast reservation or a unicast        reservation with said devices 411. In a first embodiment of the        invention the WUSB devices support at least the implicit DRP        reservation mechanism. This requires the devices to listen to        the beacons of other devices and to store the occupancy of all        data slots during the superframe. This allows the devices to        eventually reject the multicast reservation request of the WUSB        host and to eventually propose an alternative reservation time.        In a second embodiment of the invention, the WUSB devices do not        need to support the full DRP-functionality and just copy the DRP        reservation information element from the beacon of the WUSB host        into their own beacon.    -   If WUSB host or devices do not support micro-scheduling during        multicast DRP reservations, the WUSB host initiates a unicast        DRP negotiation 407 and starts WUSB operation by using Poll        Frames during the DRP reservations 409 according to another        embodiment.

It should be appreciated that, to satisfy the requirements of deviceswith different capabilities, a combination of all mechanisms may beperformed in parallel by the WUSB. Also it is possible that the WUSBhost uses EDCA access to deliver traffic or to poll connected devices406, even though a DRP reservation was established 409 410. This isuseful for scenarios were there are interferences and channel errors andthe time during the DRP reservation cannot be used.

While the preferred embodiments of the present invention have beenillustrated and described, it will be understood by those skilled in theart that the superframe as described herein is illustrative and variouschanges and modifications may be made and equivalents may be substitutedfor elements thereof without departing from the true scope of thepresent invention. In addition, many modifications may be made to adaptthe teachings of the present invention to a particular situation withoutdeparting from its central scope. Therefore, it is intended that thepresent invention not be limited to the particular embodiments disclosedas the best mode contemplated for carrying out the present invention,but that the present invention include all embodiments falling with thescope of the appended claims.

1. A method for host-device communication (103) in a first WUSB network(100) including a host (101) and at least one connected device (103),comprising the steps of: beaconing (402) according to a distributed UWBMAC protocol by the host and the at least one connected device;receiving by the host DNT traffic (403) (405); and operating the WUSBnetwork by the host according to the capabilities of the connecteddevices (406) (409) (410).
 2. The method of claim 1, further comprisingthe step of, if distributed reservation is supported, setting an offsetfield and a duration field in a DRP reservation to a multiple of apredetermined value.
 3. The method of claim 2, wherein the predeterminedvalue is 625 usec.
 4. The method of claim 1, further comprising the atleast one connected device (102) performing one of the steps of: i.using DRP access to indicate traffic; ii. using EDCA to sendnotification traffic; and iii. signaling in the beacons to sendnotification traffic.
 5. The method of claim 1, wherein said beaconingstep further comprises the steps of: including in a host beaconcapabilities of the host (402); and including in a connected devicebeacon capabilities of the at least one connected device.
 6. The methodof claim 1, further comprising the step of the at least one connecteddevice (102) discovering the host (101) via the host beacon.
 7. Themethod of claim 1, wherein the operating step further comprises the stepof if the connected device supports EDCA, the host performing the stepsof: using an EDCA mechanism to access the medium (406); polling the atleast one connected device (102) to request that the at least oneconnected device (102) transmit data; and receiving data from the atleast one connected device (102) as a result of the poll.
 8. The methodof claim 7, further comprising the at least one connected device (102)performing one of the steps of: using DRP access to indicate traffic;using EDCA to send notification traffic; and signaling in the beacons tosend notification traffic.
 9. The method of claim 1, wherein theoperating step further comprises the step of if the connected device(102) supports Unicast DRP, performing a Unicast reservation by the hostperforming the steps of: initiating a Unicast DRP reservation to the atleast one device to reserve channel resources for transmission of datato the host by the at least one device (407); polling the at least oneconnected device during DRP to request that the at least one connecteddevice transmit data (409); and receiving data from the at least oneconnected device at a result of the poll.
 10. The method of claim 9,further comprising the at least one connected device (102) performingone of the steps of: using DRP access to indicate traffic; using EDCA tosend notification traffic; and signaling in the beacons to sendnotification traffic.
 11. The method of claim 1, wherein the operatingstep further comprise es the step of if the connected device (102)supports Multicast DRP, performing a Multicast reservation by the host(101) performing the steps of: reserving channel resources in a firstDRP reservation by inclusion of multicast DRP in beacons to achieve afirst reservation (408); for each connected device that is anon-accepting device that does not accept the Multicast DRP reservation,initiating regular DRP negotiation with each non-accepting device toachieve at least one of a Unicast reservation for each non-accepting anda second DRP reservation (411); micro-scheduling the channel resourcesof the first and second DRP reservation among those connected devices ofthe at least one connected device that accept the multicast DRPreservation (410); and receiving data from the at least one connecteddevice.
 12. The method of claim 11, further comprising the at least oneconnected device (102) performing one of the steps of: using DRP accessto indicate traffic; using EDCA to send notification traffic; andsignaling in the beacons to send notification traffic.
 13. The method ofclaim 12, wherein the initiating regular DRP negotiation step further(411) comprises the step of performing at least one of the steps ofinitiating a Unicast DRP reservation with a non-accepting device andinitiating a second Multicast DRP reservation with non-acceptingdevices.
 14. The method of claim 13, further comprising the step of theat least one connected device (102) acting as a host (101) in secondWUSB network.
 15. The method of claim 14, wherein the at least oneconnected device (102) acting as a host (101) of the second WUSB networkperforms at least some of the steps performed by the host (101) of thefirst WUSB network.
 16. The method of claim 15, further comprising thestep of if distributed reservation is supported setting an offset fieldand a duration field in a DRP reservation to a multiple of apredetermined value.
 17. The method of claim 16, wherein thepredetermined value is 625 usec.
 18. The method of claim 13, furthercomprising the step of if distributed reservation is supported settingan offset field and a duration field in a DRP reservation to a multipleof a predetermined value.
 19. The method of claim 18, wherein thepredetermined value is 625 usec.
 20. A host apparatus (300) forhost-device communication in a first WUSB network including the host(101) and at least one connected device (102), comprising: a transmitter(301) for sending beacons, traffic notifications, medium reservationsand data; a receiver (304) for receiving beacons, traffic notifications,medium reservations and data; a host data transfer processing component(303 a) that processes data transferred between the host (101) and theat least one connected device (102); and a controller (302) operablycoupled to the transmitter (301), receiver (304) and host data transferprocessing component (303) and configured to direct the transmitter(301), receiver (304) and host data transfer processing component (303)to— start beaconing according to a distributed UWB MAC protocol andannounce host capabilities (402), receive and process according to adistributed UWB MAC protocol, beacons of the at least one connecteddevice (102) including capabilities of the at least one device, receiveand process DNT traffic (405), and start and control WUSB operation ofthe network (406) (409) (410).
 21. The host apparatus of claim 20,wherein the controller (302) is further configured to direct thetransmitter (301), receiver (304) and host data transfer processingcomponent (303) to: include multicast DRP in beacons and then startmicro-scheduling operation if multicast DRP is supported (410); receiveand process DNT traffic (405) and if only unicast DRP is supported bythe connected device negotiate unicast DRP (407) with the at least oneconnected device (102) and then start WUSB operation (409); and receiveand process DNT traffic (403) and if only EDCA is supported by theconnected device start WUSB operation with poll frame using EDCA (406).22. The host apparatus of claim 20, wherein the controller (302) isfurther configured to direct the device data transfer processingcomponent (353) to set an offset field and a duration field in each DRPreservation to a multiple of a predetermined value if distributedreservation is supported.
 23. The host apparatus of claim 22, whereinthe predetermined value is 625 usec.
 24. The host apparatus of claim 20,wherein when the connected device (102) only supports EDCA, thecontroller (302) is further configured to control the operation of thehost by directing the receiver (304), transmitter (302) and host datatransfer processing unit (303) to: use an EDCA mechanism to access themedium (406); poll the at least one connected device (102) to requestthat the at least one connected device transmit data (406); and receivedata from the at least one connected device as a result of the poll. 25.The host apparatus of claim 20, wherein the connected device (102)supports Unicast DRP the controller (302) is further configured tocontrol the operation of the host (101) by directing the receiver (304),transmitter (302) and host data transfer processing unit (303) to:initiate a Unicast DRP reservation (407) to the at least one device toreserve channel resources for transmission of data to the host (101) bythe at least one connected device (102); poll the at least one connecteddevice (120) during DRP to request that the at least one connecteddevice (102) transmit data (409); and receive data from the at least oneconnected device (102) at a result of the poll.
 26. The host apparatusof claim 20, wherein the at least one connected device (102) supportsmulticast DRP and the controller (302) is further configured to controlthe operation of the host (101) by directing the receiver (304),transmitter (302) and host data transfer processing unit (303) to:reserve channel resources in a first Multicast DRP reservation byinclusion of multicast DRP in beacons to achieve a first reservation(408); for each said at least one connected device (102) that is anon-accepting device that does not accept the first Multicast DRPreservation, initiate regular DRP negotiation with each non-acceptingdevice to achieve at least one of a Unicast reservation for eachnon-accepting and a second DRP reservation (411); micro-schedule thechannel resources of the first and second DRP reservation among thoseconnected devices of the at least one connected device that accept themulticast DRP reservation (410); and receive data from the at least oneconnected device.
 27. The host apparatus of claim 26, wherein regularDRP negotiation comprises at least one of negotiation of a Unicast DRPreservation with a non-accepting device and a second Multicast DRPreservation for non-accepting devices.
 28. A method for host-devicecommunication in a WUSB network including a host and at least oneconnected device, comprising the steps of: beaconing according to adistributed UWB MAC protocol by the host and the at least one connecteddevice; the host establishing a multicast reservation between the hostand the at least one connected device; and running a WUSB protocolinside the multicast reservation.
 29. The method of claim 28, whereinthe establishing and running steps each further comprise the steps ofreserving channel resources by inclusion of a multicast reservationinformation element in beacons to achieve a first reservation;micro-scheduling the channel resources of the multicast reservationamong those connected devices of the at least one connected device thataccepted the multicast reservation; and receiving data from the at leastone connected device.
 30. The method of claim 29, wherein the reservingstep further comprises the steps of: initiating a unicast reservationwith a non-accepting device; and initiating a second multicastreservation with a plurality of non-accepting devices.
 31. The method ofclaim 28, further comprising the step of setting an offset field and aduration field in a reservation to a multiple of a predetermined value.32. The method of claim 30, wherein the predetermined value is 625 usec.33. The method of claim 28, further comprising the at least oneconnected device performing one of the steps of: using DRP access toindicate traffic; using EDCA to send notification traffic; and signalingin the beacons to send notification traffic.
 34. The method of claim 33,wherein said beaconing step further comprises the step of including in ahost beacon capabilities of the host and in a connected device beaconcapabilities of the at least one connected device.
 35. The method ofclaim 33, further comprising the step of the at least one connecteddevice discovering the host via a host beacon.
 36. A method forhost-device communication in a WUSB network including a host and atleast one connected device, comprising the steps of: beaconing accordingto a distributed UWB MAC protocol by the host and the at least oneconnected device; establishing unicast reservations between the host andthe at least one connected device; and running a WUSB protocol insidethe unicast reservations.
 37. The method of claim 36, wherein theestablishing and running steps each further comprise the steps of thehost initiating a unicast reservation to the at least one connecteddevice to reserve channel resources for transmission of data to the hostby the at least one connected device; the host polling the at least oneconnected device during the reservation to request that the connecteddevices transmit data; and the at least one connected devicetransmitting data to the host as a result of the poll.
 38. The method ofclaim 36, further comprising the at least one connected deviceperforming one of the steps of: using DRP access to indicate traffic;using EDCA to send notification traffic; and signaling in the beacons tosend notification traffic.
 39. The method of claim 38, wherein saidbeaconing step further comprises the step of including in a host beaconcapabilities of the host and in a connected device beacon capabilitiesof the at least one connected device.
 40. The method of claim 38,further comprising the step of the at least one connected devicediscovering the host via a host beacon.
 41. A method for host-devicecommunication in a WUSB network including a host and at least oneconnected device, comprising the steps of: the host using an EDCAmechanism to access the medium; the host polling the at least oneconnected device to request that the at least one connected devicetransmit data; and the host receiving data from the at least oneconnected device as a result of the poll.
 42. The method of claim 41,wherein the host and the at least one connected device perform the stepof beaconing in accordance with a distributed UWB MAC protocol.
 43. Themethod of claim 41, further comprising the step of the at least oneconnected device performing one of the steps of: using DRP access toindicate traffic; using EDCA to send notification traffic; and signalingin the beacons to send notification traffic.
 44. The method of claim 43,wherein said beaconing step further comprises the step of including in ahost beacon capabilities of the host and in a connected device beaconcapabilities of the at least one connected device.
 45. The method ofclaim 43, further comprising the step of the at least one connecteddevice discovering the host via a host beacon.